With the rapid development of science and technology, reseach is brisk to synthesize zinc oxide nanomaterials which are widely used in many fields such as comosite and photocatalytic materials and so on.
Microwave has been widely applied for heating, cooking, drying, pasteurization and sterilization, and recently, microwave has been extensively used for the synthesis of nanomaterial. Up to date, in many studies various shapes of ZnO multidimensional nanostructures including nanowires, nanobelts and nanoflowers and so on have been successfully synthesized using the microwave heat.
Recently, researchers from the High-Tech Research and Development Center and the Materials Science Faculty,
Zinc oxide(ZnO) has drawn a lot of attention due to its wide, direct bandgap (3.37eV) and a large exciton binding energy (60meV). It is well known that nanostructured materials have superior properties because of the large surface-to-volume ratio, a quantum confinement effect and so on. Microwave heating method has been known as one of the most effective methods for the synthesis of various kinds of ZnO multidimensional nanomaterial on a large scale. Therefore, it is an extremely important topic to make clear the growth mechanism of ZnO multidimensional nanostructure for controllable and reproductive synthesis.
In this study, we propose a new method for the synthesis of regular and renewable ZnO nanostructures by microwave heating and report the related experimental results.
First, the properties of ZnO nanostructures under different synthesis conditions were investigated. In our experiments, Si wafers were used as crucible covers, and nanorod bundles on wafers were grown regularly and uniformly. Size and shape of the grown nanostructures were found to be different depending on the position of the wafer.
Second, we have discussed the possibility of growing such uniform nanorod structures on the spherical graphite surface contained in the precursor and also synthesizing nanoneedle-like ZnO structures.
Third, based on the measurements of high-resolution scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray powder diffraction (XRD), the growth mechanism of ZnO multidimensional nanostructures was found to follow the VLS mechanism.
Results has been published in the journal "Nano" under the title of "Large-Scale Synthesis of ZnO Nanorods by Microwave Heating Method: Growth Mechanism and Possibility of Controllable Growth of Nanoneedle" (https://doi.org/10.1142/S1793292024500164).
